Analysis on the clinical features of 22 basaloid squamous cell carcinoma of the lung

BACKGROUND Basaloid squamous cell carcinoma of the lung is a rare and highly malignant tumor mostly observed in the proximal bronchi. Basaloid squamous cell carcinoma of the lung cases typically show rapid clinical progression, very poor prognosis and special pathological morphology. This project aimed to examine the clinical features of basaloid squamous cell carcinoma of the lung and the factors related to its prognosis; and to compare survival outcomes between basaloid squamous cell carcinoma and poorly differentiated squamous cell carcinomas (PDSC). METHODS Between January 2004 and December 2008, pathological sections from basaloid squamous cell carcinoma and PDSC of the lung were collected and retrospectively analyzed at Tianjin Medical University Cancer Institute and Hospital. Data analysis was performed using Statistical Package for the Social Sciences (SPSS11.0). The Kaplan-Meier method was used to calculate the survival rate. Log-rank test was used to compare the differences in survival rate between the two groups. The factors influencing prognosis were analyzed using the Cox proportional hazard model. RESULTS A total of 120 pathological sections were used in the analysis of this study-22 from basaloid squamous cell carcinoma cases and 98 from PDSC cases. Compared to the PDSC group, the basaloid squamous cell carcinoma group had a larger proportion of female patients (p = 0.001); however it had higher proportion of male smokers (p = 0.003). There were no statistically significant differences in survival rate between the two groups (χ2 = 1.200, p = 0.273). Additionally, prognosis of basaloid squamous cell carcinoma is significantly influenced by treatment mode and clinical stages of the tumor. The post-operation mortality hazard of patients treated with a combination chemotherapy and radiotherapy was 1.296 times higher than other treatment modes (p = 0.025). Increases in post-operation mortality hazard ratio were also associated with more advanced clinical stage of tumors (χ2 trend = 11.907, p = 0.000). CONCLUSIONS This study demonstrated that basaloid squamous cell carcinoma and PDSC have very similar clinical features, and there are no significant differences in survival rates between the two groups. Hence, we conclude that in the short term, the same clinical treatments and therapeutic modes can be administered to patients with basaloid squamous cell carcinoma and PDSC of the lung.